PMA-4000 with Garmin GNS-300XL GPS/Com (both installed) and SL-30 (tray and harness installed but SL-30 itself not installed). Stark Avionics did the wire harness for all avionics.
Two problems that may be related:
1) When I power up the PMA-4000 and GNS-300, the lighted Com1 and Com2 push buttons are steady. When I press the PTT button they flash as stated in PMA-4000 documentation. When I plug my Mic jack in (Peltor 7004) both the 4000 and 300 show transmit without the PTT button depressed. I have verified the wiring between the mic jacks and PTT button several times-it is per the PS Engineering Schematic and continuity checks show the wires are correct to the Mic Jack. I can pull the mic jack PTT connector away from the Headset plug and the transmit mode stops until I press the PTT button again.
I can't figure out why the PTT circuit closes when I plug the headset in and it makes contact with all three jack connectors. It behaves like the sleeve and PTT tip are connected within the headset. I can hear the "click" when I depress the PPT button both when the headset Mic is plugged in and when it is not.
2) I cannot hear myself talk thorugh the headset in any scenerio.
Any help would be very much appreciated.
This is getting frustrating.
Thanks.
Two problems that may be related:
1) When I power up the PMA-4000 and GNS-300, the lighted Com1 and Com2 push buttons are steady. When I press the PTT button they flash as stated in PMA-4000 documentation. When I plug my Mic jack in (Peltor 7004) both the 4000 and 300 show transmit without the PTT button depressed. I have verified the wiring between the mic jacks and PTT button several times-it is per the PS Engineering Schematic and continuity checks show the wires are correct to the Mic Jack. I can pull the mic jack PTT connector away from the Headset plug and the transmit mode stops until I press the PTT button again.
I can't figure out why the PTT circuit closes when I plug the headset in and it makes contact with all three jack connectors. It behaves like the sleeve and PTT tip are connected within the headset. I can hear the "click" when I depress the PPT button both when the headset Mic is plugged in and when it is not.
2) I cannot hear myself talk thorugh the headset in any scenerio.
Any help would be very much appreciated.
This is getting frustrating.
Thanks.
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